Polycyclic N-heterocyclic compounds, part 69: Synthesis of 5-amino-1,2-dihydro[1]benzofuro[3,2-d]furo[2,3-b]pyridines and their transformations to related compounds

Reaction of 3-(3-cyanopropoxy)[1]benzofuran-2-carbonitriles with potassium tert-butoxide gave 5-amino-1,2-dihydro[1]benzofuro[3,2-d]furo[2,3-b]pyridines and 5-amino-2,3-dihydro[1]benzofuro[3,2-b]oxepin-4-carbonitriles as new ring systems. Reactions of the 5-chloro derivative, obtained from 5-amino-1,2-dihydro[1]benzofuro[3,2-d]furo[2,3-b]pyridine, produced a dihydrofuran ring-opened compound and 5-substituted compounds.